HP c-tree-SQL ISQL and Tools manual Transaction Isolation Level isolationlevel, Tbl

ISQL and Tools

DISPLAY COST ON OFF

SET DISPLAY COST ON displays the values the c-treeSQL optimizer uses to calculate the least-costly query strategy for a particular SQL statement.

The UPDATE STATISTICS statement updates the values displayed by SET DISPLAY COST ON. SET DISPLAY COST OFF suppresses the display and is the default.

AUTOCOMMIT ON OFF

SET AUTOCOMMIT ON commits changes and starts a new transaction immediately after each SQL statement is executed. SET AUTOCOMMIT OFF is the default. SET AUTOCOM- MIT OFF requires that you end transactions explicitly with a COMMIT or ROLLBACK WORK statement.

TRANSACTION ISOLATION LEVEL isolation_level

Specifies the isolation level. Isolation levels specify the degree to which one transaction can modify data or database objects being used by another concurrent transaction. The default is 3. See the SET TRANSACTION ISOLATION LEVEL statement in the c-treeSQL Reference Manual for more information on isolation levels.

CONNECTION { database_name DEFAULT}

Sets the active connection to database_name or to the default connection. See the description of the CONNECT statement in the c-treeSQL Reference Manual for details on connections.

Notes

SET REPORT and SET ECHO are similar:

•SET REPORT affects the SPOOL file only, and ON suppresses statement display

•SET ECHO affects standard output only, and OFF suppresses statement display Other statements control other characteristics of an interactive SQL session:

•The editor invoked by the EDIT statement is controlled by the value of the environment variable EDITOR.

•The file to which interactive SQL writes output is controlled by the SPOOL filename ON statement.

Examples

ISQL> -- Illustrate PAGESIZE

ISQL> DISPLAY "Here's a page break!" ON PAGE ISQL> SET PAGESIZE 4

ISQL> BREAK ON PAGE;

ISQL> SELECT TBL FROM SYSTABLES; TBL

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sys_chk_constrs Here's a page break!

TBL

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